Patient-reported pain and discomfort associated with lingual versus labial fixed orthodontic appliances: a systematic review

Purpose of review To systematically compare pain outcomes associated with labial and lingual fixed orthodontic appliances in patients undergoing active orthodontic treatment. A systematic review was conducted following PRISMA guidelines. Randomized clinical trials, prospective clinical controlled trials and retrospective observational studies reporting patient-reported pain were included. Databases searched included PubMed, Scopus, Web of Science, Cochrane Library, and EBSCO. Pain intensity, localization, and functional impact were extracted, and methodological quality was assessed using the Cochrane Risk of Bias 2.0 tool and Newcastle–Ottawa Scale. Due to heterogeneity in pain instruments, timing, and appliance design, meta-analysis could not be performed, and evidence certainty was evaluated using GRADE. Recent findings Thirteen studies involving 775 participants, of whom 554 underwent direct comparison between labial and lingual orthodontic treatment, were included. Pain peaked within 24–48 h post-appliance placement and declined within 7–14 days. Lingual appliances were associated with tongue pain in 94.4% of patients compared with 50.0% in the labial group, whereas lip pain (52.8% vs. 76.3%) and cheek pain (50.0% vs. 86.8%) were less frequent in the lingual group. The overall certainty of evidence ranged from low to moderate according to GRADE assessment. Summary All fixed orthodontic appliances cause transient early pain, with differences primarily in localization and functional impact. Lingual appliances pose greater early tongue discomfort and speech challenges, while labial appliances predominantly affect lips and cheeks. High-quality, standardized trials are needed to guide evidence-based appliance selection.